1. Technical Field
The present disclosure relates to image sensors, and particularly to a method for manufacturing a backside illumination image sensor.
2. Description of Related Art
A typical front side illumination image sensor is illuminated from the front (or top) side of a silicon die. Because of processing features (such as metallization, polysilicon, diffusions, etc), a light sensitive region is partially sheltered by, for example, metal wires, thereby resulting in a loss of photons reaching the light sensitive region and a reduction in a collection area for collecting the photons. This results in a reduction of an overall sensitivity of the image sensor.
Therefore, what is needed is a new method of making an illumination image sensor, which can overcome the limitations described.